Experts say the trove of about 700 nearly mint cards just might represent the greatest and rarest discovery in the sports card industry's history. The best of the collection is expected to fetch more than $500,000 at the National Sports Collectors Convention next month in Baltimore while the entire stock could bring in $3 million.

A 1910 Honus Wagner baseball cards found in the attic of a house in Defiance, Ohio.

The cards are part of a rare 30-player set distributed with caramel candy in 1910. Only 635 of the undersized rectangular cards from the E98 series were known to exist and most of those displayed significant wear -- a treasure so limited that even the most zealous collectors had long given up hope of piecing together a complete set.

"Amazing. It's just a blessing," said Mr. Kissner, 51, who owns Kissner's Restaurant in town. "My grandfather stuck it in the attic a hundred years ago and here it is now, a blessing to his grandchildren."

The cards belonged to Carl Hench, his grandfather, who ran a meat market in Defiance, 55 miles southwest of Toledo, and stockpiled the cards that came with candies at the time. Then he lost interest and placed the collection in a box in his attic, where they went undisturbed for more than 100 years.

His daughter, Jean Hench, lived in the house until she died in October, leaving the property and its contents to her 20 nieces and nephews. Mr. Kissner was named the head of the estate and helped clearing out the home.

It was not until February that one of his cousins exhumed the box that would change their lives.

At first, the family embraced the cards as a unique slice of a bygone era, but nothing more. The box remained on a dresser in the hallway for three days.

"We didn't understand their true significance," Mr. Kissner said.

But he researched the cards and learned they could be valuable. Mr. Kissner moved them to a more secure location of the house, then the vault at a local bank.

He contacted Heritage Auctions in Dallas, piquing the company's interest but also skepticism. Mr. Kissner could not sleep as he awaited the verdict, which would come when Chris Ivy, the director of sports auctions, and another staff member visited Defiance.

Mr. Ivy said it felt like he was in a movie as he arrived in blue jeans.

"You guys will stick out here if you come wearing suits," he recalled Mr. Kissner saying -- to see if this small Ohio town indeed had hidden the ultimate prize.

It was, in fact, the real thing.

Seeing the cards spread across a table on the second floor of Mr. Kissner's restaurant, Mr. Ivy knew the haul was worth millions.

They were pristine, the colors rich, the edges pointed. There, too, were cards of Wagner, nicknamed Hans, one of 15 Hall of Fame players in the set and the most valuable. One of the former Pirates star's rarest cards had sold for $2.8 million in 2007.

"We had never seen examples that looked this nice before," Mr. Ivy said.

Mr. Ivy said finding something like this is more difficult than winning the lottery.

Joe Orlando, president of Professional Sports Authenticator, confirmed the value as he graded each card on a scale of 1-to-10. He was stunned. A Cobb card, for instance, had never graded higher than a 7.

"After 21 years of grading and grading over a million cards a year, that's the highest grade ever," Mr. Orlando said. "Well, there were 16 9s in this find alone. Honus Wagner, the highest grade was a 5 before this. We graded a 10, we graded several nines, some 8s, some 8.5s.''

Mr. Orlando laughed as he continued to run off the numbers. He called the estimate of $3 million "conservative."

"We're in the business of hearing lots of stories about people claiming to have this or claiming to have that," he said. "So we're a little bit skeptical. But when the cards arrived, they were just absolutely spectacular. ... This could be considered the greatest single find of cards ever."

For Mr. Kissner, his good fortune continues to sink in. The restaurateur, who will split the money from the cards evenly with the other 19 family members who are part of the estate, spent Tuesday talking with reporters, including one from Australia. He awaited a crew from CBS that flew in to share his story on the national news.

"This is a little more than I expected today," Mr. Kissner said with a laugh.

Then again, so has it all.

"My, what more you can ask for?" he asked.

Contact David Briggs at: dbriggs@theblade.com, or 419-724-6084 or on Twitter @DBriggsBlade.

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